What are the legal modifications of off-road vehicles?

The legal modification of off-road vehicles includes the following points: 1, increase the throttle: if the intake flow is significantly increased but not controlled, the engine will knock because the fuel-air mixture ratio is too low; 2. High compression ratio and light piston: reduce the load of engine crankshaft and connecting rod, and the engine has rapid response and strong explosive force; 3. High-angle camshaft: the valve lift and opening angle are larger, ensuring more combustible mixture to enter the cylinder and smoother exhaust; 4. main reduction ratio and gear: increasing the main reduction ratio and encrypting the gear ratio of 1 ~ 4 can improve the acceleration of the whole vehicle at the expense of reducing the speed. Therefore, we can make up for the lost speed by increasing the tail teeth, encrypting the 2 ~ 4 gear ratio and thinning the 5 gear. 5. High-voltage line: replace the high-resistance fire line of the original car with the low-resistance fire line, so that the energy released by the ignition coil can be transmitted to the spark plug to the maximum extent, but beware of flashover, interference and other symptoms; 6. Balance bar: connect the vehicle shock tower to enhance the rigidity of the car body and prevent the car body from being damped or even deformed due to fierce control.